"指示曲线"及其在恢复陆相古环境中的应用

在一定条件下，选择一些能够反映一定古环境的指示性化石类型，对其百分含量经过简单的算术运算，就可以绘制出一条能够反映一定环境变化的曲线。即指示曲线。它的优点是直接利用资料、计算方法简单，因此在制作曲线时减少了可能形成新的误差的因素。结果直观、可靠，能够比较准确地进行半定量的环境解释。它的缺点是应用范围局限，只有在满足沉积连续，化石丰富和足够的采样精度的条件下、选择出正确的指示分子，得出的结论才是可靠的。

"INDEX CURVE", ITS APPLICATION IN TERRESTRIAL PALEOENVIRONMENT INTERPRETATION

Index curve is produced on the basis of the fact that plant distribution are controlled by several ecological factors, i.e. annual mean temperature, annual precipitation and its distribution, soil nature etc. To create a good index curve some fundamental requirements must be satisfied: e.g. continuous sediments with rich fossils, enough sampling resolution, etc. Right selection of index pollen types is critical in producing index curve. Those index types selected should have relatively strict environment requirements